1. Field of the Invention
The present invention is broadly concerned with a manually installable earth anchor foundation of the type useful for supporting landscape items such as lighting fixtures or electrical outlets requiring a utility source, e.g., an electrical cable or gas line. More particularly, it is concerned with a landscape foundation of this type which includes an elongated shaft having a transversely extending load-bearing member such as a helix secured thereto, and operatively coupled to an uppermost, apertured base plate; the anchor shaft and base plate are coupled together by means defining an open clearance area beneath the base plate aperture in order to facilitate placement and threading of an electrical cable or gas line upwardly through the anchor structure.
2. Description of the Prior Art
Helix-type earth anchors have long been employed in a variety of contexts, such as guy line supports, mobile home tie-down systems, or as a part of bases for electrical equipment. Generally speaking, such anchors include an elongated shaft presenting an earth-penetrating tip, together with one or more transversely extending helical blades secured to the shaft along the length thereof. Additionally, structure is provided adjacent the upper ends of the anchor shafts for coupling of a driving element thereto. In the case of large earth anchors of significant length, installation is normally effected by means of a power driven wrench. On the other hand, small earth anchors have in the past been designed for manual installation.
In one specific case, earth anchors have been employed as a part of a hold-down assembly for mailboxes. Such anchors are of the single helix variety and are equipped with an uppermost circular plate having a pair of spaced openings therethrough. A manual driving implement in the form of an upstanding handle having a lowermost plate provided with depending driving lugs is used to engage the upper circular plate of the anchor and, by rotation of the implement, screw the anchor into the earth until the circular plate thereof is substantially at grade. Thereupon, a mailbox leg may be bolted to the circular anchor plate for hold-down purposes.
Anchors of this type are deficient in the context of a landscape foundation, inasmuch as there is no provision for utility service to the supported structure. Moreover, the provision of circular driving/mounting apertures in the uppermost plate of the anchor makes it mandatory that the anchors be rather precisely positioned so as to accommodate the fixed distance between mailbox legs. That is to say, if the anchors are positioned apart even slightly greater or less than the distance between the mailbox legs, then it can be difficult or impossible to properly attach the legs to the respective upper plates of the anchors. As can be appreciated, such precise anchor placement can be especially difficult where the anchors must be manually installed.